Stationary induction apparatus



J. S. LENNOX.

STATIONARY INDUCTION APPARATUS.

APPLICATION FILED DEC.22. I920 Patented Nov. 28 1922.

H is Attorn ey.

Patented Nov. 28, 1922.

UNITED STATES PATENT OFFICE.

JOH N S. LENNOX, OF NORWICH, CONNECTICUT, ASSIGNOR T GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

STATIONARY INDUCTION APPARATUS.

Application filed December 22, 1920. Serial No. 432,418.

To all 10720921 it may concern:

Be it known that I, JOHN S. LENNOX, a subject oil? the King of Great Britain, residing at Norwich, in the county of New London, State of Connecticut, have invented certain new and useful Improvements in Stationary Induction Apparatus, of which the following is a specification.

My invention relates to stationary induc tion apparatus and has for its object an improved arrangement of parts which is economical, mechanically strong and readily n'iaiulfactured.

More particularly my invention relates to reactors which have a current limiting and protecting function and hence must not be materially damaged by overheating and must be mechanically rigid in order to withstand crushing stresses produced by short circuits or other transients.

According to the present general practice, reactors designed for this purpose not infrequently have bare conductors carried in some manner by suitable radial supports. In order to provide adequate ventilation over the turns it often occurs that there are considerable unsupported sections which may bend under the influence of the transient stresses with consequent disturbances in the subsequent action of the reactor. This, of course, may be remedied by sufficiently multiplying the radial supports; but within a certain range of sizes it is objectionable to multiply the radial supports, as it adds materially to the costs.

By my invention, however, an arrangement is provided in which the conductors supgiort one another without the provision of special radial supports, the same to be carriml on anon-combustible plastic spool which is adapted to be standardized over a considerable range of sizes. In this manner a cheap and mechanically strong device is at the same time provided.

For a more complete understanding of the nature and objects of my invention reference should be had to the following detailed description taken in connection with the accompanying drawing, in which:

Figure 1 is a view mainly in vertical section of a reactor constructed to embody my invention, while Fig. 2 is a top plan view of the same reactor.

Referring now to the drawing and to Fig. 55 1 in particular, 10 denotes a plastic spool rods 15 anchored in its ends and which are adapted to pass through corresponding openings formed in the end members 12 and 13. These rods 15 have nuts and Washers engaging with their protruding ends in order to secure the end members in place on the body portion 11.

About the cylindrical body portion 11 and spaced concentrically therefrom are a plurality of nested insulating cylinders 20 which are adapted to support the windings 21 of the reactor. Each cylinder is shown as havin a single layer of conductors wound helica ly thereon in abutting relation, the cyl nders themselves being retained in the desired concentric relation by theaid of vertical spacers 23, which are laid on the windings parallel to the geometrical elements of the cylinder and are preferably of sufficient thickness to fit snugly between the winding and the next external cylinder. The innermost cylinder 20 is also spaced from the body portion 11 by means of vertical spacers, as shown.

By this construction, it is seen that the cylinders 20 may be wound with any desired size or kind of winding independently and are then ready for assembly on the body portion 1. l. of the reactor, the cylinders being put in place before at least one of the end members is finally secured in place. The cylinders are themselves preferably formed of non-combustible insulating material; while the windings thereon have a non-combustible insulating covering such as asbestos, and may be connected in any desired manner, here assumed to be in series.

In order to provide ventilation for a reactor constructed in this manner, the end members are provided with perforations 30 disposed near their peripheries as shown. In order further to distribute in an approximately uniform manner the incoming air entering a perforation in the lower member to the ducts between the cylinders 20, the

members 12 and 13 are provided with radial recesses 31 on their inner faces about the openings 30, as shown. These recesses permit-the incoming volume of air to distribute itself into parallel streams traversing substantially all the ducts between the cylinders in the neighborhood of an opening 30. The superposition of the openings in the upper member 12 over those in the lower member 13 tends to produce a chimney etiect inducing a rapid circulation-of the air (or whatever the surrounding insulation medium may be) over the windings of the reactor.

The terminals of the assembled winding may be brought out through selected ones of the openings 30 as indicated in Fig. 2 at 3 a and 35.

In order to provide the reactor, assembled above described, with a suitable lifting means, I provide a centrally disposed rod or bolt which passes through openings 41 and 4:2 in the upper and lower members 12 and 13 respectively'and retain the same in place by a nut and washer 43 at its lower end and a suitable eye-nut at its upper end. This construction serves to assist in holding the parts together and by means of the eye at 45 provides a lifting means which does not strain the originalsecuring devices during a lifting operation.

The construction above described is substantially fire-proof and is well adapted to withstand the crushing stresses occasioned by short circuits and like transients; since such stresses can only tend to pinch the conductors on the cylinders 20 closer together without any consequent effects on the operation o1 the reactor. Moreover the cylinders 20 and body portion 11 may be made in any desired lengths to produce reactors of different ratings over a given range for given standardized end members.

Having now described an embodiment of my invention which is at present the best means known to me for carrying the same into effect, I would have it understood that this is merely illustrative and that I do not mean to be limited thereby to the precise details shown, nor restricted in the choice of recognized equivalents except as defined in my claims hereunto annexed,

What I claim as new and desire to secure by Letters Patent of the United States, is

A reactor comprising a plastic non-combustible insulating spool composed of a body portion and separable end members, means for independently securing said end members'to the body portion, spaced concentric insulating cylinders surrounding said body portion, and windings on eachof said cylinders, said end members having openings near their peripheries and in line with the spaces between said insulating cylinders to admit a cooling and ventilating medium through said spaces.

In witness whereof, I have hereunto set my hand this 18th day oi iDecember, 1920.

JOHN S. LEN NOX. 

